Best Koi Food for Enhancing Color and Maximizing Growth

Seeing your Koi rise to the surface to feed is one of the best parts of being a Koi owner. But feeding your Koi is also one of the most important and tricky parts of taking care of your fish.

What you’re feeding your Koi makes a huge difference in how they grow, the color of their scales, and how healthy they’ll be.

That’s why it’s so important to understand what you should be feeding your Koi to keep them happy, healthy, and looking their best.

To help, I’ll cover everything you need to know about how to feed your Koi – from what affects how Koi process food to the additives you can use to encourage beautiful colors in your Koi.

I’ll also review eight of the best Koi foods that you can feed your fish to maintain their well-being and color.

Product Comparison Table for Koi Food

Last update on 2024-04-18 / Commissions Earned / Images from Amazon Product Advertising API

What Do Koi Fish Eat?

Koi fish are omnivores with a pretty strong digestive system. So, they’ll eat just about any natural foods that you give them as long as they’re small enough to swallow.

In the wild, Koi fish eat algae, insects that land on the water’s surface, leaves and other plant debris, and even animal feces.

In captivity, you can feed Koi a huge variety of foods. They will eat fruits and vegetables, as well as carbohydrate-rich foods like cereal, bits of bread, and rice. They will even eat some types of small protein, such as shrimp or cut-up pieces of chicken.

Ultimately, just like people, Koi need a balanced diet of carbohydrates and proteins with a little fat.

If you’re feeding your Koi multiple times per day, you can mix up which meals are rich in carbohydrates and which are rich in protein. Or, if you get a standardized Koi food, it will have enough of both for your fish.

How Does Food Affect Koi Fish Color?

Food contains many vitamins that affect the pigments in a Koi’s scales – which in turn affects the color of your fish.

In general, red is the color most easily affected by food in Koi because many commercial Koi foods contain varying amounts of carotenoids.

These vitamins add to the orange, yellow, and red colors of your Koi fish, and giving your fish enough carotenoids can even begin to turn white spots to pink.

However, don’t expect new food to change the color of your fish immediately. Managing the color of your koi through food requires multiple feeding over days and weeks.

How to Choose Koi Food to Maximize Health, Growth, and Color?

Choosing the right food for your Koi is an essential part of maximizing their health, growth, and color.

Although there are numerous types of commercial Koi food on the market, many of the cheap foods don’t contain the right mix of carbohydrates, proteins, nutrients, and vitamins to allow your Koi to grow to their best.

There are two common additives in Koi food to keep an eye out for.

Spirulina is a type of algae that can improve the red color of your Koi because it contains a high level of carotenoid vitamins.

Spirulina is rich in protein and is also good for your Koi’s immune system, which is why many Koi owners prefer food with this additive in it.

However, feeding your Koi too much Spirulina can actually cause the color of your fish to become too red and white spots to turn pink.

Wheat germ oil is another common additive, which is rich in fats and oils that give your Koi a shining appearance.

Because wheat germ oil is high in fat, it is often used for growing Koi so that they have plenty of energy to reach their maximum sizes.

Pro Tip: wheat germ oil can be somewhat expensive, since it is also a popular human supplement, so many Koi foods use carbohydrate-rich wheat germ with the oil pressed out instead.

There are a number of other types of food that can be healthy for Koi while promoting their coloration. Krill, for example, also include carotenoids that enhance the color of your fish while serving as a nutritious protein source.

You can also add specific vitamins to your fish’s food, such as certain types of carotenoids or other pigments, to improve their color.

Factors that Affect Koi Feeding

There are a number of factors that affect how and what you should feed your Koi. That’s because these fish are constantly growing and their digestive requirements change with the water and weather conditions.

Koi Size

The size of your Koi affects the size of their mouth and digestive tract. So, smaller fish will need smaller food pellets and larger fish will need larger food pellets.

As a rule of thumb, fish that are three inches or smaller will do best with tiny sinking pellets that are 3/32” in diameter or smaller. Larger fish, such as fish longer than four inches, will have better eating habits with floating pellets that are 3/16” in diameter.

If your Koi are eight to 10 inches or longer, you should opt for fish pellets that are ¼” in diameter or up to 5/16” in diameter.

Season

The levels of carbohydrates versus proteins that your Koi need in their food varies with the temperature of your Koi pond. That’s because Koi tend to be more active in cold water than in warm water due to the change in oxygen content.

In the winter, when the water is cold, Koi will be very active and hungry. In this case, you should feed them food with high levels of carbohydrates and low protein content, such as wheat germ.

Wheat germ in particular is easy for Koi to digest while they are actively swimming around and won’t pollute the water as much as a protein-rich food.

In the summer, when the water is warm, Koi will slow down and will need higher levels of protein to maintain their body and to grow optimally. In this season, you’ll likely want to switch to a food with higher levels of Spirulina or krill as a protein source, and to stay away from food rich in wheat germ.

In the fall and spring, when temperatures are intermediate or changing, you will want to give your Koi a mix of carbohydrate- and protein-rich foods.

You can either use a food that offers a balanced diet, or feed your Koi two different types of food in the morning and afternoon.

Temperature

While the seasons are a good guide as to how to balance carbohydrates and protein in your Koi’s food, you can also measure the temperature of your water to determine how to feed your fish.

Carbohydrate-rich diets are appropriate when the water temperature is colder than about 50 degrees Fahrenheit.

Protein-rich diets are better for your Koi when the water is warmer than about 70 degrees Fahrenheit. At intermediate temperatures, you can provide a mix of carbohydrates and proteins.

Weather Influencing Oxygen Content

Oxygen content is a major influence on how your Koi will digest food and what type of food is appropriate to feed them. In turn, weather can play a big role on the oxygen content of your pond’s water.

When it is raining out, the oxygen content of the ambient air actually drops slightly. Unless your pond is very deep, that will also decrease the oxygen content of the water.

In that case, your Koi will be less active than they usually are. You’ll likely want to feed them slightly less than normal, and to switch temporarily to a more protein-rich diet.

Sunny weather can also reduce the oxygen content of the water by heating up your pond. As discussed above, warmer water has less oxygen, so your Koi will be better off with a protein-rich diet.

Water Quality and Pumps Affecting Oxygen Content

Keeping high water quality is also extremely important in maintaining the oxygen content of your pond. Algae can produce oxygen when they’re growing at the surface, but once they die they sink to the bottom.

Microbes feeding on those dead algae can then suck huge amounts of the oxygen out of the water, leaving your Koi in a low-oxygen situation.

On the other hand, if you use pumps, you may artificially increase or decrease the oxygen content of your pond’s water.

Turning on the pumps will prevent algae from growing by circulating the water, while also aerating the pond’s water and adding oxygen. In this case, your Koi will likely be more active and a carbohydrate-rich food will be more appropriate.

8 Best Koi Food on the Market Reviewed

Since so many things can affect what your Koi need to eat, there are a huge variety of Koi foods available on the market. But many Koi foods don’t have the right balance of carbohydrates, proteins, and nutrients.

Here, we’ll take a look at eight of the best foods you can feed your Koi to keep them happy and healthy.

1. Shinju White Pearl Enhancer Wheat Germ (All Season)

• Pellet Size: Medium
• Season: All seasons (above 50F)
• Protein: 38%
• Fat: 3%
• Ash: 11%
• Vitamins: A, C, D3, E, K, and minerals
• Color Enhancer: No

This wheat germ-based food pellet is designed to preserve the white coloration of your Koi’s scales while providing them with a healthy balance of carbohydrates and proteins.

The food mixture has a 38% protein content, most of which comes from fish meal. This relatively high protein content makes it a great choice for feeding your Koi in the spring and fall, and depending on the temperature variation in your pond the food can be used throughout the year.

In addition, the food mix has a 3% fat content thanks to residual oil contained in the wheat germ.

The food mixture is otherwise pretty basic, with no added color enhancer like Spirulina or immune boosting components.

That said, it does have plenty of vitamins and minerals to keep your Koi healthy on their own, and the basic mixture of this food means it is a good all-around choice for keeping your Koi growing and active.

Last update on 2024-04-18 / Commissions Earned / Images from Amazon Product Advertising API

2. Shinju Color Pearl Enhancer Premium Koi Fish Food

• Pellet Size: Medium
• Season: All seasons (above 50F)
• Protein: 38%
• Fat: 3%
• Ash: 11%
• Vitamins: A, C, D3, E, K, and minerals
• Color Enhancer: Spirulina (4000 PPM or above)

This color-enhancing food mixture from Shinju removes some fish meal and adds in Spirulina to the company’s White Pearl Enhancer food. The overall balance of protein, fat, carbohydrates, and ash remain the same, making it a similarly good food for use throughout the season.

That said, the addition of Spirulina can make a big difference in the coloration of your Koi.

They should take on a more reddish hue, although if you see your fish’s white spots starting to turn pink you may need to supplement with White Pearl Enhancer for some meals.

Like in the other Shinju food, the food mixture relies on a balance of vitamins and minerals rather than a specific immune booster.

Note that this food is somewhat expensive because of the high Spirulina content, so you may want to supplement it with a less expensive all-season food.

Last update on 2024-04-18 / Commissions Earned / Images from Amazon Product Advertising API

3. Hikari-Saki All Season Koi Food

• Pellet Size: Medium
• Season: All seasons
• Protein: 37%
• Fat: 5%
• Ash: 15%
• Vitamins: A, C, D3, E, K, and minerals
• Color Enhancer: Spirulina and krill

This relatively inexpensive all-season food from Hikari-Saki is designed to improve the coloration of your Koi without breaking the bank.

The food mixture contains both Spirulina and krill as protein sources in addition to fish meal, which adds to the red color of your Koi without being overwhelming like the Shinju Color Pearl Enhancer food may be.

This food mixture also has a relatively high fat content of 5%, which is due to the inclusion of fish oil in the food. The primary carbohydrate source in the food is wheat germ, although there is also some rice mixed in.

Note that the ash content in this food is 15%. While ash is used to provide calcium and phosphorous, ash contents above 12% are generally thought to be unnecessary and will simply increase the amount of fish waste in your pond.

Last update on 2024-04-18 / Commissions Earned / Images from Amazon Product Advertising API

4. Dainichi Koi Premium Koi Food

• Pellet Size: Large
• Season: Summer
• Protein: 47%
• Fat: 4%
• Ash: 9%
• Vitamins: Mix
• Color Enhancer: Spirulina

This premium food from Dainichi is designed for larger Koi, specifically those greater than about eight inches in length. That’s because the food is delivered in relatively large-diameter pellets and has a high protein content of about 42%.

The protein is derived from Spirulina, which is also used for enhancing the color of your Koi, fish meal, and milk powder.

The relatively high protein content is also why this food is recommended for summer, although it could easily be used into the spring and fall as well.

There is no immune booster in this food mixture, although Dainichi includes an unspecified vitamin mix.

Interestingly, this food includes calcium montmorillonite clay, which is the same type of clay that is found in the ponds that Koi are native to. This is designed to help bind particles in the water, effectively cleaning your pond as your Koi eat.

Last update on 2024-04-18 / Commissions Earned / Images from Amazon Product Advertising API

5. TetraPond Koi Growth (Budget Friendly Option)

• Pellet Size: Medium sticks
• Season: Spring, summer, fall
• Protein: 43%
• Fat: 9.5%
• Ash: 8%
• Vitamins: C and minerals
• Color Enhancer: No

This relatively basic food mixture from TetraPond is designed for medium-sized Koi in water temperatures that are over 50 degrees Fahrenheit. The food has a relatively high protein content of 43% that is derived from fish meal and shrimp meal.

Most notably, this fish food contains soybean oil as an abundant fat source. In total, the food is roughly 9.5% fat, which is twice that seen in some of the other recommended Koi foods.

This can be healthy for growing Koi, but it also means that you may need to feed your Koi slightly less than you would with other less fat-rich food mixtures.

The other thing to note about this food mixture is that it does not contain many vitamins. The food is fortified with vitamin C, but vitamins A, D, E, and K are missing from the food mixture in appreciable quantities.

That may not make much of a difference to your Koi, but if you see them getting sick you may need to supplement with vitamins or an immune booster.

Last update on 2024-04-18 / Commissions Earned / Images from Amazon Product Advertising API

6. Kaytee Koi’s Choice Premium Fish Food (Budget-Friendly Option)

• Pellet Size: medium
• Season: All seasons (above 50F)
• Protein: 35%
• Fat: 5%
• Ash: 1%
• Vitamins: A, C, B12, K, D3 and minerals
• Color Enhancer: No

This budget friendly food provides a balance between protein, carbohydrates and fat.

But, it does have a relatively high protein content at 35%. So it’s ideal for spring and fall but can be offered year round with a careful feeding regimen.

The main carbohydrate sources are soybean meal, wheat flour, corn gluten and wheat germ meal. This mix of less expensive carbohydrates is probably what accounts for the lower price point.

It’s important to note that it does have a somewhat high fat content at 5% due to added fish oil.

It doesn’t contain any color enhancers, like carotenoids or spirulina, but it is fortified with vitamins and minerals.

A few users complain that their fish won’t eat these pellets, but the majority of reviews praise it and report good growth and great value from this food.

No products found.

7. Hikari Wheat-Germ Medium Pellet

• Pellet Size: Medium
• Season: Fall, winter
• Protein: 32%
• Fat: 4%
• Ash: 12%
• Vitamins: Vitamin and mineral mix
• Color Enhancer: Krill

This low-protein food mixture from Hikari is ideal for colder water temperatures when your Koi are more active.

For that reason, it is recommended primarily for fall and winter, although it can also be used late into the spring if you are aerating your tank with a pump.

The carbohydrates in this food come from not only wheat germ, but also wheat and rice flours.

Krill are one of the sources of protein, which can help to enhance the color of your Koi – although the effect will not be as noticeable as with a Spirulina-based food pellet.

Hikari added a vitamin and mineral mixture to the food to keep your Koi healthy.

In addition, the company notes that the food is enhanced with vitamin C, since this is one of the more important vitamins for the health of your fish. There is no specific immune booster additive, though

Last update on 2024-04-18 / Commissions Earned / Images from Amazon Product Advertising API

8. Hikari Gold Koi Fish Food

• Pellet Size: Medium
• Season: Fall, winter
• Protein: 33%
• Fat: 4%
• Ash: 17%
• Vitamins: A, C, D3 and mineral mix
• Color Enhancer: Spirulina and krill

This premium pellet food from Hikari is designed to bring out the best possible color in your Koi. The food mixture contains both Spirulina and Krill to add carotenoids, and the food contains a wealth of vitamins and minerals to bring out the shine in your fish’s scales.

The food is recommended for fall and winter primarily because of the relatively low 33% protein content.

However, it could be used throughout the year if you maintain cool water temperatures in the summer and aerate your pond with a water pump.

Note that the ash content of this food mixture is extremely high – 17% – which can create a lot of unnecessary waste in your pond.

That may not be a problem if you have a pump, but all of that phosphorous waste can otherwise contribute to the growth of algae.

Last update on 2024-04-18 / Commissions Earned / Images from Amazon Product Advertising API

Which is Best?

The best food mixture for your Koi depends on the conditions in your pond, the size of your fish, and how you want to manage your fish. For example, smaller, growing Koi will need smaller food pellets, like those offered by Total Koi.

You also need to consider whether you want to stick with a single food for the entire year, or change foods depending on the season.

If you opt for a food that is supplemented with Spirulina, like those from Hikari, Dainichi, Hikari-Saki, and Shinji, you may also want to mix in some feedings with a food that does not have Spirulina so that your fish’s white spots don’t turn pink.

Ultimately, the choice of which food is best comes down to what works for your Koi. Try out a food, and if your Koi have problems with health or color then consider switching to a more seasonally-appropriate or supplemented food source.

Last update on 2024-04-18 / Commissions Earned / Images from Amazon Product Advertising API